It wouldn’t make sense to calculate a death rate based on who died today versus how many new cases there are today. People don’t die from COVID-19 the same day they’re infected. If they did, this whole thing would have burned out extremely fast. It takes 14-16 days on average from infection to death with COVID-19.
There are two ways of calculating mortality: the Case Fatality Rate (CFR), and the Infection Fatality Rate (IFR). Calculating the CFR is rather simple: you take the total number of deaths (165,829) and divide it by the number of cases (5,218,584) for a CFR of 0.03177 or 3.18%. The IFR is more complicated. For that, you need to build statistical models to determine how many actual infections have occurred rather than just the number of cases. It’s particularly difficult for COVID-19 because 35-40% of people won’t show symptoms and another 40-45% won’t be sick enough to need medical assistance, so you’re missing a lot of cases. To fix that, you have to tie in data from antibody testing and use areas with a more isolated and easily studied population groups.
The IFR for COVID-19 has been calculated by numerous studies and the CDC as being between 0.64% and 0.66%. You’ll notice that’s much lower than the CFR, but also higher than the seasonal Influenza CFR of ~0.1%. Seasonal flu’s IFR is calculated to be between 0.025%-0.04% depending on the particular season, strain, etc. The CFR for Malaria is 0.3%, 1-3% for Measles, and it was 11% for SARS 2003. Incidentally, that last one is why SARS 2003 burned out: it didn’t spread particularly well, but for those it did spread to, symptoms were often quite severe with a significant risk of death.
It’s a trend analysis - 1% death rate from the flu is calculated from the SEASON and as more people get infected (especially those not in nursing homes) the rate has been trending lower which is bringing it down from 6% to now 3% and continues to fall. For my state we’ve had an increase of infected to almost 1000 a day but the death rate has fallen to under a dozen a day and as low as 1. Now this changes a little over time as some deaths are back dated but the trend line is still falling to zero as infection rates increase.
If this virus were as deadly as it’s hyped and claimed we be seeing a spike in deaths as well.